Book/Report

FZJ-2018-04520

http://join2-wiki.gsi.de/foswiki/pub/Main/Artwork/join2_logo100x88.png Response function of the trigger scintillation detector for the COSY 11 installation

Moskal, P. (Corresponding author)FZJ*

1993
Forschungszentrum Jülich GmbH Zentralbibliothek Verlag Jülich

Please use a persistent id in citations: http://hdl.handle.net/2128/19436

Report No.: Juel-2825

Abstract: Thorough investigations carried out over many years revealed, that the hadronic matter is certainly mach richer than the simple constituent quark model expectation with only three quark and quark- antiquark hadrons. The QCD theory predicts the existence of hadronic objects, other than the known baryons and mesons, like glueballs and hybrids (q$\overline{q}$g). Presently available data, however, does not provide sufficient information to judge, for instance, whether f$_{o}$ (975) and a$_{o}$ (980) mesons reveal q$\overline{q}$, qq$\overline{q}\overline{q}$ or K$\overline{K}$ molecular structure. Their small two-photon partial width $\Gamma_{\gamma \gamma}$ and a very narrow full width [2] still remain unexplained. Further, there exists some recent theoretical predictions [1] that s$\overline{s}$ quarks constitute only 50% of the $\varnothing$(1020) meson, which is generally regarded to possess pure s structure. However, so far this is not confirmed experimentally. Equally interesting is a discussion of the gluon content of eg. the $\eta$' (958) meson [1]. A few attempts were made to predict theoretical glueball masses, but the results are model dependant [2]. Thus, investigations which can prove the existence of the exotic quark states are presently of significant interest in medium energy physics. In order to find an answer to sonne of the above mentioned problems the detection systern, sketched in Fig. 0.1, has heen designed. Soon it is to be installed in the $\underline{c}$ooler $\underline{s}$ynchrotron ring (COSY) at Jülich, which will provide a high quality proton beam with proton momenta up to 3,3 GeV/c. Experiments are planned to allow the study of the structure of resonances in pp $\rightarrow$ ppM$^{0}$ and pp $\rightarrow$ pnM$^{+}$ reactions with meson masses up to the meson $\varnothing$(1020) and also investigations an meson - meson or meson - nucleon final state interaction via reactions of the type pp $\rightarrow$ ppM$_{1}$M$_{2}$. The aim of this work is to test the response of a scintillation detector (indicated in Fig. 0.1 as S1 to ionizing particles. This counter, consisting of sixteen detection modules, will serve as a trigger of the whole detection system. Thus the time resolution as well as a signal amplitude variation with respect to a hit position is of a special interest. The former because this detector will be used as a statt counter for the time of flight measurement, the atter as it will provide energy loss measurements of the particles. The present work is divided into two parts. In the first one the main stages of a signal production by scintillation Counters are considered. In the second one the first chapter presents measurements of the characteristics of the photomultiplier, whereas the second one contains a description of the experimental set-ups as well as the method of data evaluation. The final chapter in turn presents the main characteristics of the considered detector.

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Contributing Institute(s):

1. Publikationen vor 2000 (PRE-2000)

Research Program(s):

1. 899 - ohne Topic (POF3-899) (POF3-899)

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